I'm starting to suspect bad contact or trace somewhere. If I lift the board a bit or even tap disk drive instant restart/freeze. If trying to load a game it loads few secs but then stops.
Remove every chip, clean if necessary and inspect all pins and sockets. it smacks of bad contacts, pay attention especially to Agnus(cracked sockets are common).
The cpu socket also.
I've had a a3000t that had a bad socket that was broken underneath between board and socket and you couldn't see it at all. really fun to find it, i spent a hour with it running prodding with a plastic stick on sockets and chips till i made it crash. It was a factory defective socket that just happened to act up when i got the machine.
Bad psu voltages on the +5 rail can also make a machine crash and or boot random.
